#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <iostream>
using namespace std;
#define BUF_SIZE 1024

int main(int argc, char **argv)
{
    int serv_sock, clnt_sock;
    char message[BUF_SIZE];
    int str_len, i;
    struct sockaddr_in serv_adr;
    struct sockaddr_in clnt_adr;
    socklen_t clnt_adr_sz;
    FILE *readfp;
    FILE *writefp;
    if (argc != 2)
    {
        printf("Usage : %s <port>\n", argv[0]);
        exit(1);
    }
    serv_sock = socket(AF_INET, SOCK_STREAM, 0);
    if (serv_sock == -1)
    {
        cerr << "socket() error" << endl;
        exit(1);
    }
    memset(&serv_adr, 0, sizeof(serv_adr));
    serv_adr.sin_family = AF_INET;
    serv_adr.sin_addr.s_addr = INADDR_ANY;
    serv_adr.sin_port = htons(atoi(argv[1]));
    if (bind(serv_sock, (struct sockaddr *)&serv_adr, sizeof(serv_adr)) == -1)
    {
        cerr << "bind() error" << endl;
    }
    if (listen(serv_sock, 5) == -1)
    {
        cerr << "listen() error" << endl;
    }
    clnt_adr_sz = sizeof(clnt_adr);
    for (i = 0; i < 5; i++)
    {
        clnt_sock = accept(serv_sock, (struct sockaddr *)&clnt_adr, &clnt_adr_sz);
        if (clnt_sock == -1)
        {
            cerr << "accept() error" << endl;
        }
        else
        {
            printf("Connected client %d \n", i + 1);
        }
        readfp = fdopen(clnt_sock, "r");
        writefp = fdopen(clnt_sock, "w");
        while (!feof(readfp))
        {
            fgets(message, BUF_SIZE, readfp);
            fputs(message, writefp);
            fflush(writefp);
        }
        fclose(readfp);
        fclose(writefp);
    }
    close(serv_sock);
    return 0;
}